半人马座 A 喷流中至甚高能的加速分辨
高能天体物理现象
2020-07-10 v1 星系天体物理
摘要
邻近射电星系半人马座 A 属于一类在射电波段极亮的活动星系。这类星系中的大多数显示出称为喷流的准直相对论性外流，对于最强大的源，其延伸超过数十万秒差距。物质吸积到中心超大质量黑洞被认为为这些喷流提供燃料并驱动其辐射，其中射电辐射与磁场中相对论性电子的同步辐射相关。从这些源的千秒差距尺度喷流中看到的延展 X 射线辐射的起源仍存争议，尽管 Cen A 的 X 射线辐射被认为起源于电子同步辐射过程。另一种可能的解释是与 CMB 软光子的逆康普顿（IC）散射。同步辐射需要极端相对论性电子（ TeV），并且鉴于其较短的冷却时间，需要某种连续的再加速机制处于活跃状态。另一方面，IC 散射不需要能量极高的电子，但要求喷流在 large scales（1 Mpc）上保持高度相对论性且与视线保持良好对准。一些近期证据不利于逆康普顿-CMB 模型，尽管其他证据似乎与之相容。原则上，延展伽马射线辐射的探测——直接探查极端相对论性电子的存在——可区分这些选项，但仪器迄今未能分辨相关结构。在 GeV 能量下，Cen A 还存在一种不寻常的谱硬化，其解释尚不清楚。本文我们报道在 TeV 能量下对 Cen A 的观测，分辨出了其大尺度喷流。我们将数据解释为喷流中极端相对论性电子加速的证据，并支持 X 射线的同步辐射解释。
引用
@article{arxiv.2007.04823,
title = {Resolving acceleration to very high energies along the Jet of Centaurus A},
author = {The H. E. S. S. Collaboration and : and H. Abdalla and R. Adam and F. Aharonian and F. Ait Benkhali and E. O. Angüner and M. Arakawa and C. Arcaro and C. Armand and H. Ashkar and M. Backes and V. Barbosa Martins and M. Barnard and Y. Becherini and D. Berge and K. Bernlöhr and R. Blackwell and M. Böttcher and C. Boisson and J. Bolmont and S. Bonnefoy and J. Bregeon and M. Breuhaus and F. Brun and P. Brun and M. Bryan and M. Büchele and T. Bulik and T. Bylund and M. Capasso and S. Caroff and A. Carosi and S. Casanova and M. Cerruti and T. Chand and S. Chandra and A. Chen and S. Colafrancesco and M. Curyło and I. D. Davids and C. Deil and J. Devin and P. deWilt and L. Dirson and A. Djannati-Ataï and A. Dmytriiev and A. Donath and V. Doroshenko and L. O'C. Drury and J. Dyks and K. Egberts and G. Emery and J. -P. Ernenwein and S. Eschbach and K. Feijen and S. Fegan and A. Fiasson and G. Fontaine and S. Funk and M. Füßling and S. Gabici and Y. A. Gallant and F. Gaté and G. Giavitto and D. Glawion and J. F. Glicenstein and D. Gottschall and M. -H. Grondin and J. Hahn and M. Haupt and G. Heinzelmann and G. Henri and G. Hermann and J. A. Hinton and W. Hofmann and C. Hoischen and T. L. Holch and M. Holler and D. Horns and D. Huber and H. Iwasaki and M. Jamrozy and D. Jankowsky and F. Jankowsky and A. Jardin-Blicq and I. Jung-Richardt and M. A. Kastendieck and K. Katarzyński and M. Katsuragawa and U. Katz and D. Khangulyan and B. Khélifi and J. King and S. Klepser and W. Kluźniak and N. Komin and K. Kosack and D. Kostunin and M. Kraus and G. Lamanna and J. Lau and A. Lemière and M. Lemoine-Goumard and J. -P. Lenain and E. Leser and C. Levy and T. Lohse and I. Lypova and J. Mackey and J. Majumdar and D. Malyshev and V. Marandon and A. Marcowith and A. Mares and C. Mariaud and G. Martí-Devesa and R. Marx and G. Maurin and P. J. Meintjes and A. M. W. Mitchell and R. Moderski and M. Mohamed and L. Mohrmann and C. Moore and E. Moulin and J. Muller and T. Murach and S. Nakashima and M. de Naurois and H. Ndiyavala and F. Niederwanger and J. Niemiec and L. Oakes and P. O'Brien and H. Odaka and S. Ohm and E. de Ona Wilhelmi and M. Ostrowski and I. Oya and M. Panter and R. D. Parsons and C. Perennes and P. -O. Petrucci and B. Peyaud and Q. Piel and S. Pita and V. Poireau and A. Priyana Noel and D. A. Prokhorov and H. Prokoph and G. Pühlhofer and M. Punch and A. Quirrenbach and S. Raab and R. Rauth and A. Reimer and O. Reimer and Q. Remy and M. Renaud and F. Rieger and L. Rinchiuso and C. Romoli and G. Rowell and B. Rudak and E. Ruiz-Velasco and V. Sahakian and S. Saito and D. A. Sanchez and A. Santangelo and M. Sasaki and R. Schlickeiser and F. Schüssler and A. Schulz and H. M. Schutte and U. Schwanke and S. Schwemmer and M. Seglar-Arroyo and M. Senniappan and A. S. Seyffert and N. Shafi and K. Shiningayamwe and R. Simoni and A. Sinha and H. Sol and A. Specovius and M. Spir-Jacob and Ł. Stawarz and R. Steenkamp and C. Stegmann and C. Steppa and T. Takahashi and T. Tavernier and A. M. Taylor and R. Terrier and D. Tiziani and M. Tluczykont and C. Trichard and M. Tsirou and N. Tsuji and R. Tuffs and Y. Uchiyama and D. J. van der Walt and C. van Eldik and C. van Rensburg and B. van Soelen and G. Vasileiadis and J. Veh and C. Venter and P. Vincent and J. Vink and F. Voisin and H. J. Völk and T. Vuillaume and Z. Wadiasingh and S. J. Wagner and R. White and A. Wierzcholska and R. Yang and H. Yonedak and M. Zacharias and R. Zanin and A. A. Zdziarski and A. Zech and A. Ziegler and J. Zorn and N. Żywucka},
journal= {arXiv preprint arXiv:2007.04823},
year = {2020}
}
备注
32 pages, 5 figure